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Although high-temperature superconductor cuprates have been discovered for more than 25 years, superconductors for high-field application are still based on low-temperature superconductors, such as Nb(3)Sn. The high anisotropies, brittle textures and high manufacturing costs limit the applicability of the cuprates. Here we demonstrate that the iron superconductors, without most of the drawbacks of the cuprates, have a superior high-field performance over low-temperature superconductors at 4.2 K. With a CeO(2) buffer, critical current densities >10(6)  A cm(-2) were observed in iron-chalcogenide FeSe(0.5)Te(0.5) films grown on single-crystalline and coated conductor substrates. These films are capable of carrying critical current densities exceeding 10(5) A cm(-2) under 30 tesla magnetic fields, which are much higher than those of low-temperature superconductors. High critical current densities, low magnetic field anisotropies and relatively strong grain coupling make iron-chalcogenide-coated conductors particularly attractive for high-field applications at liquid helium temperatures.

Purpose This study aims to acquire a better understanding about consequences of workplace incivility upon restaurant frontline service employees caused by customers, supervisors and coworkers. The moderating roles of perceived organizational support (POS) and emotion regulation ability (ERA) were also tested to determine the possibility for reducing the negative effect of workplace incivility upon the emotional exhaustion of restaurant frontline service employees. Design/methodology/approach Using data obtained from 239 restaurant frontline service employees, a 35-item instrument was used to assess workplace incivility and its effects upon emotional exhaustion, perceived service performance, POS and ERA. A structural equation model was used to test hypotheses. The multi-group approach was used to investigate the moderating effects POS and ERA have upon the relationships between workplace incivility, emotional exhaustion and perceived service performance. Findings Results documented that workplace incivility significantly increases emotional exhaustion and further leads to low levels of job service performance. Customer incivility was especially found to have the strongest power for increasing emotional exhaustion, followed by supervisor incivility. Also, results confirmed that POS and ERA play significant roles in moderating the relationships between workplace incivility, emotional exhaustion and perceived service performance. Based upon this study’s findings, theoretical and practical implications are offered for developing successful employee management strategies. Practical implications Results suggest specific practical management implications pertaining to restaurant frontline service employees. This study’s research findings recommend the development of more efficient support programs designed to diffuse potential situations involving workplace incivility. Findings further highlight the important role employee ERA has upon the effects of incivility and frontline service performance. Implications are provided with respect to specific strategic direction management should consider to recruit and select the most appropriate employees for restaurant frontline service positions. Originality/value The current study’s conceptual research was developed in an attempt to simultaneously address all three dimensions of workplace incivility to examine how they affect employee emotions and their job performance.

Salen-type ligands comprised of ethylenediamine or 1,2-cyclohexenediamine, along with an salicylaldehyde bearing a methyl substituent on its 3-position and a -[CR(CH(2)CH(2)CH(2)N(+)Bu(3))(2)] (R = H or Me) on its 5-position, unexpectedly afford cobalt(III) complexes with uncoordinated imines. In these complexes, two salen-phenoxys and two 2,4-dinitrophenolates (DNPs), which counter the quaternary ammonium cations, coordinate persistently with cobalt, while two other DNPs are fluxional between a coordinated and an uncoordinated state in THF at room temperature. The complexes of this binding mode show excellent activities in carbon dioxide/propylene oxide copolymerization (TOF, 8300-13,000 h(-1)) but with some fluctuation in induction times (1-10 h), depending on how dry the system is. The induction time is shortened (<1.0 h) and activity is increased approximately 1.5 times upon the replacement of the two fluxional DNPs with 2,4-dinitrophenol-2,4-dinitrophenolate homoconjugation ([DNP...H...DNP](-)). Imposing steric congestion either by replacing the methyl substituent on the salicylaldehyde with tert-butyl or by employing H(2)NCMe(2)CMe(2)NH(2) instead of ethylenediamine or 1,2-cyclohexenediamine results in conventional imine-coordinating complexes, which show lower activities than uncoordinated imine complexes.

The synthesis of the first examples of anion receptors that utilize boron–fluoride interactions and (C–H)+···F–‐type ionic hydrogen‐bond interactions in the binding of F ions is reported herein. o‐, m‐, and p‐Phenylboronic acids were linked to naphthoimidazolium through a methylene group. On the basis of fluorescence and 19F NMR studies, we have confirmed that the addition of fluoride to a boron center occurs prior to the formation of (C–H)+···F–‐type ionic hydrogen bond with the imidazolium moiety. More importantly, these investigations have demonstrated that only the receptor bearing the ortho‐directed boron and imidazolium exhibits enhanced fluoride binding. The increased binding ability of the asymmetric bidentate receptor of ortho‐boronic acid and imidazolium towards F– enables it to sense fluoride ions in a 95:5 CH3CN/HEPES aqueous solution. The fluorescence responses to different anions were also explored; the ortho‐boron‐imidazolium receptor displayed ratiometric fluorescence changes and a high selectivity towards fluoride ions over other anions (Cl–, Br–, CH3CO2–, HSO4–, and H2PO4–).(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

We present an experimental study of the anisotropic resistivity of superconducting La2−xBaxCuO4 with x = 0.095 and transition temperature Tc = 32 K. In a magnetic field perpendicular to the CuO2 layers, H ⊥ , we observe that the resistivity perpendicular to the layers, ρ ⊥ , becomes finite at a temperature consistent with previous studies on very similar materials; however, the onset of finite parallel resistivity, ρ , occurs at a much higher temperature. This behavior contradicts conventional theory, which predicts that ρ ⊥ and ρ should become finite at the same temperature. Voltage vs. current measurements near the threshold of voltage detetability indicate linear behavior perpendicular to the layers, becoming nonlinear at higher currents, while the behavior is nonlinear from the onset parallel to the layers. These results, in the presence of moderate H ⊥ , appear consistent with superconducting order parallel to the layers with voltage fluctuations between the layers due to thermal noise. In search of uncommon effects that might help to explain this behavior, we have performed diffraction measurements that provide evidence for H ⊥ -induced charge and spin stripe order. The field-induced decoupling of superconducting layers is similar to the decoupled phase observed previously in La2−xBaxCuO4 with x = 1/8 in zero field.

A carbonyl group was positioned between 1,8-naphthalimide and di-2-picolylamine (DPA) and played a key role of displaying fluorescence enhancements with heavy and transition metal (HTM) ions through increasing the oxidation potential of the fluorophore, blocking HTM ions from sterically interacting with the naphthalimide fluorophore, and by acting as a sacrificial donor.

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